Buttonhole sewing machines



A. H. DE VOE.

BUTTONHOLE SEWING MACHINE.

APPLICATION man 1150.31.1915. RENEWED 11111. 1.1921.

WITNESSES:

A TTORNEY A. H. DE VOE.

-BuTIoNHoIE SEWING MACHINE.

' APPLICATION FILED DEC. 31.`I9I5. IIENEwED IAN. 7, 1921. 1,416,004.

Patented May 16, 1922.

14 SHEET SHEET 2.

WITNESSES A. H. DE VOE.

BUTTONHOLE SEWING MACHINE.

APPucATloN flu-:n Dic. 31, |915. nEnEwED JAN. 1. 1921.

1 ,41 6,004. Patented May 16, 1922.4

14 SHEETS- SHEET 3.

A. H. DE VOE.

BUTTONHOLE SEWING MACHINE.

APPLICATION msn 211.31.1915. nsnewso JAN. 1.19m.

1,416,004, Patented May 16, 1922.

I4 SHETS-SHEET 4.

[NVE/WOR WITNESSES:

A. H. DE VOE.

uTToNHoLE SEWING MACHINE.

APPLICATIQN FILED )EC'31,1915 RENEWED IAN. 7.1921.

Patented May 16, 1922.

I4 SHEETS-SHEET 5.

A. H. DE VOE.

BUTTONHOLE SEWING MACHINE.

APPLICATION FlLED DEc.31.1915. RENEWED JAN. 7. 1921..

1 ,416,004, Patented May 16, 1922.

14 SHEETSwSHEET 6.

WITNESSES.- l/v VE/v mi? v ATTORNEY Muff/M@ e Patented May 16 1922.

14 snEETs-SEET 7.

TTOHNE Y A. H. DE VOE. -uoNHoLE SEWING MACHINE.

APPLICATION-FILED DEC. 31.1915. RENEWED JAN. 7. 1921.

Patented May 16, 1922.

I4 SHEETS-SHEET 8.

Wl TNESSES:

A TTOHNEY l VA. H. DE voE.

BUTTONHOLE SEWING MACHINE.

APPLICATION FILED DEC-3l. 15H5.V RENEWED IAN. 1.

Patented May 16, 1922.

I4 SHEETS--SHEET 9.

A. H. DE VDE.

BUTTONHOLE SEWING MACHINE.

APPLICATION 111m 11Ec.a1,1915. RENEwED 1AN. 1. 1921.

. Patented M1'1y16,1922.`

14 SHEETS-SHEET l0.

A. H. DE vos. BUTTONHOLE SEWING MACHINE. APPLICATION FILED DEC- 31, 1915. 4IIEIIEWED JAN. 7. 192|- 1,416,o04, Patented Mayl, 1922.

I4 SHEETS-SHEET I I.

A. H. DE vos'.

`BUTTONHOLE SEWING MACHINE.

APPLICATION man DEc.31.1915. nENEwEn JAN. 1.1921.

Patented May 16, 1922..

INVENTOH w/rA/Essfs:

A; #W @QM l TTRNEY A. H. DE voE. BUTTONHOLE SEWINGv MACHINE. APPLICATION FILED DEC- 31,1915. RENEWED JAN. 7.-l92l.

Patented May 16, 1922.4

14 snzsrgzguagl 1a.

IVVENTOH A. H. DE VOE.

BUTTONHOLE SEWING-MACHINE.

APPLICATION man 0m31.191s. RENEwED JAN. 7. 192i.

Patented May 16, A1922.'

I4 SHEETS-SHEET I4.

A TTR/VEY UNITED STATES PTENT FFCBV,

ALBERT H. DE VOEE E' W'ESTFIELD, NEW JERSEY, ASSEGNB, TO THE 'SINGER MANU- FACTURENG- COMPANY, .A CORFORlfllOliT` OF NEXV JERSEY.

BUTTONHOLESE`WING MACHINE.

Application led December 31, 1915, Serial No. 69,644. Renewed January 7, 1821. Serial 110.4315361.

To all '107mm t may concern:

lie it known that l, ALBERT H. Dn Von,

a citizen oi the United States, residing at lllestfield, in the county of Union and State oi New Jersey, have invented certain new and useful improvements in uttonholewing` .Ti/lachines, oi which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to an improvement more particularly in that class of buttonhole sewing machines employing stitching mechanism adapted to perform a semi-rotation ior production oi radial stitches at one or both ends of hnttonhole in conjunction with the nsnal straight line of side-stitches produced hy the relativ-e feed of the stitch-forming mechanism and the work; and it has for its primary object to increase the capacity of production as Compared with buttonhole machi .s atpresent in commercial use, and also to 'acilitate the control oi the machine under all conditions in the handling of the work by (the operator- .ln the preferred embodiment of the pres. ent invention, the control of the entire mechanism is centralized in a member of the starting device by which, not only are the starting and stopping ci the several operative portie -s ci the machine effected in the required order, but one or more of such portions of the machine may be stopped or otherwise rendered ineii'ective in suitable order emergency. such, for instance, as the tweaking of a stitching thread. The invention also preferably includes a special construction and arrangement of travelling buttonhole cutting device with actuating means whereby preparatory to its travel from retracted position it is caused to yieldingly nip the work and carry it bodily from. one position to another relatively to thest1tchinoj t and the required positioningy of the bn onholes to he formed therein. The present invention Further includes preferred novel construe fis of the needle mechanism l f .ing dwices with the means "Arcy are given their turning moveie end stitching portions of a but- Y (fing-cycle. rlhe invention inrri ir includes a preferred special construction of the work-clamp with its operating .means designed ifor use particularly in conmechanism for effecting the spacingjunction with the work-shifting buttonhole cutting mechanism.

The'invention will be understood by reference to the accompanying drawings, in which- F ig. l and Fig. 2 an elevation taken from the opposite side of a buttonhole sewing machine em' bodying the present improvements. Fig. v3 is a plan, Fig. 4 a front end viewand Fig. 5 a rear end view of the machine. Fig. v6 is a sectional elevation representing the feedwheel and the cutter-actuating cam and portions of the mechanism associated therewith. Figs. 7 Vand 8 are perspective Views representing the feed-wheel and portions of the'y mechanism for controlling the action of the same and other parts of the machine. Fig. 9 is a perspective view representing` the clutch mechanism and its controlling devices whereby the operative parts oit' the machine are connected with the source of power; and Figs. 10, 11, 12, 13, 14, 15 and 16 are perspective views of rdetached parts of the clutch mechanism. Figs. 17 and 18 (sheet 2) are respectively a side elevation and a transverse sectional view of the operative parts of one oic the clutches; and Fig. 19 (sheet 4) is an elevation, with the driving wheel in section, showing the relation of the operative parts of the two clutches through which power is transmitted from the driving wheel for actuation o'f the several groups of mechanism of the machine.

Fig. 2O is a perspective view representing a part ot' the controlling mechanism for the driving device. F ig. 2i is a perspective view of the bnttonhole cutting mechanism, and Figs. parts of said mechanism. Figs. 25 and.26 are respectively a plan and elevation, partly in section, representing the machine bed, the stitching iframe and a portion of the feeding mechanism.

F i g. 27 is a perspective view representing the machine bed, the stitclriramc, and the worlcclamp with its actuating means, and Figs. 28 and 29 are similar views showing parts oit the work-clamp mechanism. Fig. El() (sheet is a plan of the feed-wheel and certain parts ci the work-clamp mechanism and Fig. 31 is a perspective view of certain elements of the same. Figs. 32 and 33 (sheetl) are respectively a plan and elevation ci is an elevation taken from one side,

Specification of Letters Patent. Patint-@d lWay 16,

22, 23 and 24 are details of certain'` the work-clamp and the buttonhole cutting device in cut-ting position. Fig. 34 is a perspective view, taken from the under side, of one of the lower work-clamp members, and Figs. 35 and 36 are perspective views taken respectively from the upper and lower sides, of the other" lower work-clamp member. Fig. 37 is a detail sectional view of a part of the device for turning the stitch-forming mechanism.

Fig. 38 is a plan of the stitch-frame and the loop'er mechanism with its actuating means, and Fig. 39 a sectional elevation representing the looper mechanism. Fig. 4G is a plan of the looper mechanism and its supporting turret detached, and Fig. 41 an elevation of the same with certain parts omitted. Fig. 42 is an elevation taken from the front of the machine and representing the stitch-frame and the stitch-forming mechanism, and Fig. 43 is a similar view of the same parts taken from the same side of the machine as in Fig. 2. These figures are upon a larger scale than Figs. 1 to 6, and represent the stitch-frame partly in section. Figs. 44, 45 and 46 are perspective views respectively of the turret sustaining the looper mechanism, the lower thread carrying needle with its supporting and actuating means, and the spreader with its supporting and actuating means.

Fig. 47 is a cross-section of the needle-bar and needle-'actuating bar with their connections, and Fig. 48 is a perspective view of certain parts of the latter. Figs. 49, 50, 51 and 52 are transverse sectional views showing certain parts, of the looper-actuating mechanism in di'erent operative positions, and Figs. 53, 54 and 55 are perspective views representing said parts detached.

Figs. 56, 57, 58 and 59 are perspective views showing diagrammatically the stitchforming elements in different stages of a stitch-forming cycle and a portion of an edge-covering seam as applied to the margin of a buttonhole slit formed in the fabric.

The machine frame is constructed with the bed-plate 1 having the depending legs 2 and the standards 3 and 4 at opposite edges connected by the cross-member 5. The standard 3 is] shown provided with a. laterally'extending bracket 6 formed with a bearing boss 7 in which and a bearing boss 8 is journaled the rotary shaft 9 which drives the stitch-forming mechanism and which is surrounded by a tubular shaft 10 for driving the feeding and buttonhole cutting mechanisms, which shaft is journaled in a bearing boss 11 of the cross-member 5.

Loosely mounted upon the reduced outer end portion 10 of the shaft 10 is the hub 12 or' the peripherally grooved belt-wheel 13 formed in its opposite Llaces with annular clutch-cavities 14 each opposed to a similar brake cavity 15 of one of the hollow bosses 16 of the bearing bracketl 6 and frame boss 11, respectively (Figs. 4 and 10).

The shafts 9 and 19 carry adjacent and upon opposite sides ot the driving pulley 13 suitable clutching and braking devices which are similar in construction, except in being in right-and-leit arrangement, and therefore a description of the one will apply equally to the other.

The shaft 9 is shown having lixed thereon within the brake-cavity 15 ot the bracket 6 the hub 17 of a disk 18 formed upon its inner face with a boss 19 affording peripheral brake-band and clutch-band seats 2O and 21 and cut out at one side to form a segmental recess 22.

The seat 20 has secured thereon by screws 23 one end, suitably apertured, ofi the brakeband 24. having an enlarged opposite extremity 24l recessed to receive the anti-friction roller 25 mounted upon the bearing stud 26 tapped into the part 24', which lies normally within and in braking relation with the inner wall ot' the surrounding brake-band cavity 15. The seat 21 has secured thereon by screws 27 one apertured extremity of the similarly formed clutch-band 23 having its opposite end 28 recessed in its inner face to receive the anti-friction roller 29 journaled upon the bearing stud 30 tapped into said end of the clutch-band. this clutch-band being normally embraced by but maintained out of contact with the walls of the adjacent clutch-cavity 14 of the belt-wheel 13.

The boss 19 of the disk 13 is cut away upon the side opposite the recess 22 to receive the angular clutch-lever 31 having an aperture 32 to receive a ulcrum-.stud 33, by means of which it is pivotally mounted within a slot of said boss between the seats 2O and 21. The lever 31 carries upon opposite faces and at opposite sides ot' the fulcrum-aperture 32 the laterally projecting roller-studs 34 and 3, the 'former working in the radial slot 18 of the disk 13 and being adapted to contact with the roller :.5 ot the brake-band and the latter to engage' the roller 29 of the clutch-band.

That arm of the clutch-lever 31 carrying the roller-stud has a substantially segmental extension 36 formed at its. extremity with an inwardly extending lug 37 entering the cavity 22 of the disk 18 in which latter is secured by means ot a screw 33 a thrustblock 39. Between the bottom or' a cavity in the thrust-block 39 and the lug 37 is interposed a spring 40 which acts upon the clutchlever to torce the stud 35 into engagement with the clutch-band roller 29 and to retract the stnd 34 from contact with the brake-band roller 25.

The clutch-lever extension 3G is if'ormed with an outwardly projecting portion 41 passing` through the clearance notch 42 ot the clutch-band seat 21 and the notch 43 of the CII clutch-band 28 yand aiiording an inclined hearing shoulder for engagement with the similarly inclined edge of an inwardly eX- tending` lug of one of the segmental thrustblocks i5 secured by meansot screws i6 upon opposite sides ot the rim of the driving pulley 13. -lli/'Then the elutchlever Si is tree to turn upon its fulorum-stud. 333 under the action of the spring` a0, the projection rests upon the inner wall of the clutclrcavity 14. of the driving wheel until it comes into register with the clearance notch 47 therein (Fig. 15), through which it emerges to permit a clutchingaction of thelever 31 which is thus caused to thrust the stud 35 into engage/ment with the roller 29 to expand the clutch-band 28 into gripping relation with the wall of the clutch-cavity. slip of the clutch-band upon the driving wheel is arrested by the engagement et the projection 4-1 with the lug` List extending` into the notch e7, whereby, not only is the clutchlever thrust still more Vforcibly into clutch-` ing relation, but a positive coupling,` is insured between the driving and driven members. i 1

The clutch-lever arm sustaining the rollerstud 35 has .a second outwardly 'projecting portion 48 which entends through notches t9 and 50 in the adjacent edges of the brake and clutch-bands 24C and 28 and between the adjacent edges of the rims ot' the bosses, 16 and the driving` wheel 13 beyond which latter it presents an eccentrically arranged segmental bearing surface e8 to provide for actuation of the clutch-lever i'rom the eX- terior of the clutch device,

The bosses 16 containing` the brake-band cavities are provided each with 'an upwardly extending lug` y51 in which is mounted the rocleshaft 52 having ournaled thereonor independent movement the hubs 53 and 5a of two rock-levers spaced apart by mea-ns of the intermediate collar 55. These rochlevers each comprise a tappet-arm 56 forked at its outer extremity to embrace a roller 57 sustained therein upon the journalepin 58.V The rollers 57 are disposed each above one of the spaces between the driifing wheel and one of the bosses 16,y (Fig. a) and therefore above the paths of movement of the clutchlever extensions i8 into and out'oi ment with which they are designed for` movement. These rocl-levers are provided with oppositely extendingV armsv 59 each pivotally connected by means et a pin 6G lwith one end of ay linlr 61 havingr its opposite end connected by a pin 62 with one of the levers 63 and 64, the former being' fixed upon an inner rocleshait 65 and the latter upon a tubular rock-shaft 66 surrounding the same.

The inner rock-shaft 65 is journaled at its opposite ends within a bearingy 67 entend. ing from the outer brake-band boss 16 and,

a bearing 68 or "the, iframe crossfmember 5 The initialV (Fig. 3), andthe tubular rock-shaft 66 is journaled internally upon the rock-shaft 65 and externally within a bearing 69 extend laterally from the inner brake-band boss 16 and the trame standanl 3. The links 61. and the 63 and 641- form lbetween .the

roch-levers 5&1-, 56 and 59 and their respective rock-shafts toggle devices o'liwhich the extreme operative positions are determined by the angularly arranged stop-arms 70 and 71 (Figs. 9 and 10) each secured to and movable with its respective toggle arm by means of ascrew. 72. Each ot the arms TO and 71 carries a stop-screw 755 and "ffl, respectively, adapted to contact with the exterior of the boss 16 for determining the throw oi' the link 64A.

TWhen either toggle is bent under the action of the spring 75 interposed between the stop-arm 70 and the adjacent boss 16, the roller 57 is retracted, and its respective clutch-lever is permitted to revolve with the driving wheel,unobstructedly; but when the toggle is straightened as represented particula-rly in Figs. 9 and 10, the roller 57 is moved inwardly into the peripheral clearance notch 16 of the boss 16, and into the path or' movement of the extensions 48 of its respective clutch-lever, thereby thrusting the same inwardly to shift the clutch-lever tor uncoupling its respective shaft from the driving wheel and applyingv the brake in the manner before described.

As the outer end portion of the bearing face a8 of the clutch-lever extension 1S extends slightly beyond the roller 57 even when the rollerstud 3a engages the` brake band roller Q5 (Fig. 16) it is evident that the roller 57 imposes a positive barrier to the continued rotation of the clutch-lever with its connected shaft, and therefore positively` brings the latter to rest always in the same position, so thatr the positions of restoi' the moving parts are invariably the same. lt is also evident that, although the shafts 9 rind 10 are adapted to be coupled independently to the common driving wheel 13, the clutching devices act, as previously described, to couple them to the driving member in such manner that they invariably assume fixed relation during a working` cycle, which isla. matter oit importance in buttonhole sewing machines involving the action offdifferent work-engaging elements upon the fabric in succession in substantially the same woiling` position.

lnoosely journaled at one end upon the tubularrock-shaft 66 and at the other 'end upon the concentric inner shaft 65 is a rocking sleeve 7 6 provided rintermediate its ends with the spaced laterallyy projecting' tappetf arms 77 and 7 8, the arm v78 having' an extension formed with yoke 79 which em 10. The sleeve 76 is cut away on one side intermediate its ends to expose the inner end of the tubular rock-shaft 66 and the adjacent portion of the rock-shaft 65, which have secured thereon by means of set-screws 81 and 82 the hubs of two laterally extending arms 83 and 84 each disposed adjacent one of the tappeti-arms 77 and 78.

Each of the armsl 83 and 84 has tapped into its upper face a shouldered stud-screw 85 entering the apertured boss 86 of a laterally movable latch-lever 87. Each lever 87 has its end portion adjacent the sleeve 76 notched in one side and the reduced portion 87 thus formed extended within a. housing afforded by a lug 88 and overhanging lip 89 formed upon the adjacent tappetarm, a spring 90 being interposed between the parts 87 and 88 to normally maintain the latch-lever in superposed relation and alinement with its supporting arm, and with a depending stop-flange 87 thereof in contact relation with the edge of said supporting arm which is notched to receive the same.

Under the action of their respective springs 90, the latch-levers are normally maintained out of the range of action of the adjacent tappet-arms 77 and 78, and the arms 83 and 84 may assume their lower positions in which the toggles 61 and 64 are bent; but when the latch-levers 87 are shifted laterally in opposition to such springs, as represented at the left in Fig. 9, they are caused to project above the respective tappet-arms, which perform constant rising and falling movements during the operation of the machine, and are thereby lifted so as to straighten said toggles and tilt the rocklevers 56 59 into stopping position.

The ends of the latch-levers 87 opposite their notched extremities project in different degrees beyond the corresponding ends of the arms 83 and 84, the one sustained by the arm 83 being the shorter of the two. In the elevated positions of the said arms assumed while the machine is at rest, the overhanging portions of the levers 87 rest upon the ends of the spaced members of a yoke 91 at the upper end of a detaining arm 92 secured by screws 93 upon a plate 94 extending upwardly from a collar 95 fixed upon the endwise movable starting rock-shaft 96 in the bearing bracket 97 secured to the front side of the frame cross-member 5.

The rock-shaft 96 is shown having secured upon one end the split hub 98 of a lateral crank-arm 99 carrying a crank-pin 100 embraced by a strap at the upper end of a treadle-rod 101, by which the rock-shaft may be rocked in starting the machine to retract the detaining yoke 91 for disengagement of one of its members with the shorter of the latch-levers 87 to permit its carrying arm 83 to descend for bending the inner toggle to effect the coupling of the tubular shaft 10 with the driving pulley. A subsequent endwise movement of the shaft 96 causes the edgewise shifting of the detaining yoke and consequent disengagement of the other member thereof from the longer latch-lever 87 to effect the coupling of the shaft 9 with the driving pulley.

The collar 95 carries a depending pin 102 which enters an elongated aperture 103 in a substantially segmental cam-lever 104 having at one end a lateral extension 105 formed with an apertured boss 106 entered by the fulcrum stud-screw 107 which is tapped into the depending block 108 carrying the transverse fulcrum-pin 109 (Figs. 8 and 20) which is journaled in a suitably apertured bracket-piece 110 secured to the standard 111 which depends from the bearing bracket 97. The angularly arranged fulcrum-pins 107 and 109 form a universal-joint connection of the cam-lever 104 with its supporting frame whereby such lever is adapted for movement both horizontally and vertically.

The concave edge 104 of the cam-lever and the overhanging angular edge 112 of the cam-plate 112 secured by screws 113 thereon are adapted for engagement by a stud 114 upon a block 115 secured by screws 116 upon the upper face of a gear-wheel 117 which is in turn secured by screws 118 upon the upper face of the feed cam-cylinder 119. The cam-cylinder 119 is formed with a hub 119 fitted upon a tubular bushing 120 having at its lower end the flange 121 to support the weight of the cam and secured within a hub 122 of the frame cross-member 5 by means of set-screws 123, of which only one is shown in Fig. 6.

Meshing with the gear-wheel 117 is a driving pinion 124 secured upon the lower end of the cutter-actuating shaft 125 journaled in the bearing bosses 126 and 127 having fixed thereon the worm-wheel 128 meshing with the worm 129 formed in the tubular shaft 10. By the means described the shaft 10, which rotates in unison with the driving pulley 13, turns the cutter-shaft 125 at a reduced speed through the described worm and worm-wheel connection and the feedcam is driven at a still slower speed by its speed-reducing gear connection with the cutter-shaft.

The starting rock-shaft 96 has secured upon its end; opposite the crank-arm 99 the split hub 130 of a block 131 having a transverse slot in which is secured by means of the pivotal screw-pin 132 the forwardly] extending starting lever 133 having a rearward extension 134 of reduced width. The hub 130 is formed with a socket between the bottom of which and the adjacent edge of the lever 133 is interposed a spring 135 (Fi 9) by which the edge of the lever is yieldingly maintained in contact with the inner end of the embracing slot of the block 131 (Fig. 7).

The extension 134 of the starting lever entere and engages the upper wall of a recess 136 of a lifting Slide-plate 137" formed with a slot 138 to receive a screw 139 by which it is slidingly sustained upon an upright seat upon the frame-member 5. The plate 137 is formed with a forked lateral extension 140 embracing the free end portion of the camplate 104 (Fig. 8). The lifting plate is normally pressed downwardly by means of avspring 141 surrounding a pin 142 entering a socket in a frame-member 143 between which and the lifting plate the spring is interposed.

The rock-shaft 96 has loosely mounted thereon the hub 144 of a rock-lever having a lateral arm 145 and an oppositelyextending arm formed with a yoke 146. The hub of this lever rests against the adjacent member of the bearing bracket 97, and has interposed between it and the hub 98 of the crank-arm 99 a spring 147 by means of which the rock-shaft 96 is pressed endwise in the direction indicated by the arrow in Fig. 20, and through the pin-and-slot connection 102 103 the cam-lever 104 is yieldingly maintained within the range of movement of the stud-pin 114 moving with the cam-wheely 119.

The collar 95 is formed with a laterally notched and forwardly projecting finger 148 which, under the normal action of the spring 141 upon the extension 134 of the starting lever, is normally pressed upwardly in contact with the bottom of the anglepiece 149 secured upon the standard 111 by screws 150, (Figs. 8 and 20). The operative end of this angle-piece is formed with la socket containing the headed plunger-pin 151 with its lower end normally projecting below the bottom of the angle-piece under the action of the flat spring 152 overlying the angle-piece and pressing upon the head of the plunger-pin.

lVhen the starting rock-shaft 96 is in initial position in which the yoke 91 detains the clutch-controlling levers 83 and 84 in elevated position, the finger 148 occupies the position beneath. the angle-piece 149 represented in Fig. 20, the lower end of the plunger-pin resting upon such linger. When, however, the rock-shaft 96 performs its twostep endwise operative movement underthe action of the stud-pin 114 successively upon the cam edges 104 and 112', the finger 148 is moved edgewise in a. direction opposite to that indicated by the arrow in Fig. 20, and the plunger-pin 151 descends under the action of its spring 152 into latching relation with the linger, as indicated in Fig. 7

The finger 148 remains in engagement with the detaining plunger-pin 151 until the shaft 96 is rocked by means of the treadl rod 101 or the nger-lever 133 at the beginning of a succeeding working cycle, when the finger 148 becomes disengaged from the plunger-pin 151 and is permitted under the action of the spring 147 to reassume its initial positionbeneath the same.

The rocking of the starting shaft96 by depression of the crank-arm 99 or finger-lever 133 not only causes the disengagement of the yoke 91 from one of the latch-levers 87 to effect the starting of the tubular shaft 10 which drives the cam-wheel 119, but acts through the extension 184 of the lever 133 to raise the lifting plate 137 in opposition to its spring 141, thereby lifting the cam-plate 112 out of engagementwith the stud-pin 114 with which it remains in engagement at the completion of a working cycle, thereby permitting the starting shaft 96 to perform one step of its operative movement under the action of the spring 147 and bring the operative edge of the camlever 104 into engagement with the studpin 114.

In this position of the shaft 96, the second of the yoke-members 91 is still beneath'the longer of the latch-levers 87 but as the studpin 114 performs its travel with the supporting cam-wheel, it rides off the end of the cam-lever 104 and thereby further rem oves the restraint upon the shaft 96 against the second stage of its endwise clutch-controlling movement under the action of the spring 147. Y In performing the second stage of its movement, the shaft 96 carries the yoke 91 from beneath the latch-lever 87, thereby permitting the arm 84 to descend and thus effect the coupling of the shaft 9 with the driving pulley to set the stitchforming mechanismin operation.

The starting lever extension 134 normally rests against the body of the lifting plate 137 as indicated in Fig. 8, not only when the parts are in stopping position but after the :initial actuation of the starting rock-shaft 96. The second stage of endwise movement of the shaft 96 carries the lever 133 bodily with it to bring the extension 134 into contact relation with the depending lip 137 affording the opposite wall of the recess 136 where it remains during the stitching operation.

In order to stop one or both trains of mechanism actuated by the shafts 9 and 10 during a working cycle of the machine, the starting lever 133 may be manually shifted edgewise in the direction of the arrow (Fig. 7) to move the rock-shaft 96 toward initial position in opposition to its spring 147. This movement of the shaft acts, similarly to the corresponding movement automatically effected by means of the stud-pin 114 and the cam-lever 104, to bring the edge of the appropriate member of the yoke 91 against the adjacent edge of the longer latchlever 87 to laterally shift the same into engagement with the tappet-arm 78 for lifting the arm 84 to uncouple the shaft 9 from the driving` pulley7 the raising of the latch-lever 87 with its supporting arm permitting it when in its highest position to snap into initial posit-ion above' its actuating yoke-member under the action of the spring 99.

A continued movement of the starting lever 133 in the same direction produces a like engagement of the other detaining yokemember 91 with the shorter latch-lever 87 for uncoupling the shaft 10 from the driving pulley. It is evident that the elements 87 and 91 are spaced apart sufficiently and are of the requisite width to permit the described successive control of the clutchcontrolling arms 83 and 84.

As represented in the drawings, the cutting device is mounted to perform travelling movements from retracted position into and out of the range of operation of the stitchforming mechanism which preferably includes a reciprocating eye-pointed upper needle n, a reciprocating' curved and eyepointed lower needle orlooper Z, and a spreader s for seizing thread-loops from the upper needle and holding them below the work for passage of the lower needle which presents loops of its own thread above the work for passage of the upper needle. 1n the present embodiment of the invention, the stitchforming elements are sustained by a travel.- ling stitch-frame adapted to be shifted out of its normal working position to permit the cutting of a buttonhole slit in stitching position.

The cutting device comprises a vertically and horizontally movable cutter-lever formed in two rigidly connected sections 153 and 154 with an intermediate raised seat 155 apertured to receive and guide a. stud 156 and a steady pin 157 depending from a plate 158 having an upwardly offset lateral extension 159, (Figs. 21 and 33). Secured upon the extension 159 by means of screws 160 is the cutter-block or plate 161 disposed beneath and in operative relation with the relatively movable upper cutting knife 162 secured by a screw 163 upon an overhanging member 164 of the cutter-lever arm 154.

The cutting elements 161 and 162 .are normally mantained separated by means of a spring 165 surrounding the stud 156 and interposed between the head of a screw 166 tapped therein and the lower fac-e of the member 155 of the cutter-leif'er.

The cutter-lever arm 153 is formed with a transverse boss 167 in which is secured by set-screws 168 the pivotal pin 169 which is journaled in the spaced members of a transverse yoke 170 of a swinging frame 171 carrying the guide-rod 172. The frame 171 is formed with a depending boss 173 embraced between and pivotally connected by means of the pin 174 with the spaced arms 175 of a link member which arms are rigidly connected together by a tie-piece 176. The arms 175 embrace between them and are pivotally connected by means of the pin 177 with the spaced lateral arms 178 of a1 swing-bracket having a tubular hub 179 journaled upon the fulcrum-stud 180 'which is sustained by the bed-plate. 1 (Fig. 1).

By the means described, the swinging frame 171 is supported for movement in any direction horizontally around the pivotal pins 174, 177 and 18() and is restrained against movement in other directions. The cutter-lever, while having a pivotal connection with said frame transverse to the pins upon which it moves, is sustained in a hori- Zontal position by reason of the screw 166 resting upon the top of the foot 300 of a bracket 301 secured upon the bed-plate 1 (Figs. 2, 4 and 5).

Slidingly mountedupon the guide-rod 172 is a sleeve 182 adapted to be secured thereon in the desired position of adjustment by means of the clamp-screw 183 and provided with a laterally extending and apertured boss 184 in which is secured by means of the set-screw 185 the fulcrum-pin 186 which enters a bushing 187 secured by means of the set-screw 188 in a lateral socket 189 of the sliding sleeve 19() (Fig. 1). The sleeve 199 is fitted upon a. guide-rod 191 of the rigid bracket 192 provided with a parallel rod 193 embraced by the wings 194 of the sleeve 190 to prevent the latter from turning, a clampscrew 195 being applied to the sleeve 190 to secure it in the desired position of adjustment.

rlhe bracket 192 is shown secured to the front end of the bed-plate 1 with the parallel rods 191 and 193 inclined to the vertical pivotal pins 174, 177 and 180. the rod 172 being so sustained by its swinging trame 171 that it assumes a position in parallelism. with the rods 191 and 198 when directly above them corresponding with the cutting` position of the cutting elements.

The vertically arranged pin 186 obviously affords a. fulcrum upon which the swinging frame 171 and the connected cutter-lever more to confine the bodily travel of the cutting elements to a circular path with a degree of curvature determined by the distance of its fulcrum-pin from cutting position with which it is maintained in alinemefnt in its adjustment along the fixed guiderod 191. By simultaneous adjustment of the sleeves 182 and 190 lengthwise of their respective supporting rods, the radins of curvature of the travellingr movements of the cutting elements may be correspomlingly varied. Y

rll'he position of the fulcrum-pin 186 relative to cutting position might be suitably varied if the guide-rods 172 and 191 were 

